Vehicle security systems are known to include electronic devices such as alarms and so called "killer switches" which directly disable the engine or ignition unless bypassed by an authorized operator with a special key or an electronic code, as well as mechanical devices such as steering wheel locks which inhibit unauthorized operation of the vehicle by constraining the steering wheel against rotation when locked into position. However, all these vehicle security systems suffer from numerous disadvantages in terms of cost, convenience and effectiveness.
Electronic alarms for motor vehicles have become well known in recent years, and so have the disadvantages associated with their use. Such alarms are specifically adapted to be highly sensitive to physical force or motion in order to sound-off when the vehicle is disturbed in any way. Consequently, such alarms are frequently activated accidentally by persons such as parking lot or service station attendants, passengers seeking entry to the vehicle, or the owners themselves who neglect to attend to the alarm upon entry of the vehicle. Furthermore, electronic alarms seem to be prone to malfunction, as most motorists have on occasion encountered a vehicle with an alarm sounding for no apparent reason.
So called "killer switches" have also become well known in recent years. These switches serve to disable the vehicle, usually at the ignition system, unless a special key or electronic code is employed to override the switch. In addition to being costly and suffering from the usual reliability problems associated with electronic devices carried on a motor vehicle, this type of security system is easily bypassed by a knowledgeable thief. Furthermore, the typical motorist is less knowledgeable regarding electronic systems and may be prevented from operating the vehicle in an emergency if the system malfunctions, or if the proper means of bypassing the system is forgotten or not known by family members or others who need to operate the vehicle.
Vehicle security systems also include mechanical anti-theft devices which restrain relative movement between the operating controls at the interior of the vehicle. Such mechanical locks comprise a pair of hooks at opposite ends of an elongated locking apparatus which is adjustable in length so that one hook can be engaged on a foot pedal and the other positioned around the steering wheel rim. The elongated apparatus is then contracted in length and locked into position to provide a rigid and tight connection between the foot pedal and the steering wheel, whereby neither of those vehicle control components can be moved relative to the other as required for operation of the vehicle. These mechanical locks provide vehicle security without the cost and complexity of electronic security systems, and further provide the convenience of being usable selectively at the discretion of the motorist as opposed to being an ever present fixture of the vehicle which must inconveniently be attended to every time the vehicle is operated.
Nevertheless, mechanical locks extending between the steering wheel and a foot pedal suffer from a serious shortcoming which substantially inhibits their effectiveness as anti-theft devices. The hooks and locks are usually composed of hardened steel to resist removal by bending or prying, and most importantly to resist cutting with a hacksaw or clipping with an oversized bolt cutter. While the locks themselves are thereby inherently resistant to destruction and removal by a thief, they fail to provide an effective overall vehicle security system since a thief may merely cut or clip the steering wheel rim to provide a severed break through which the lock hook may be removed from its secured position. Unlike severing of the foot pedal bar, severing of the steering wheel rim would barely inhibit operation of the vehicle by a thief, and likewise would barely detract from the value of the stolen vehicle.
The prior art is thus seen to fail to provide a vehicle security system which is economical, simple, and convenient to use, and yet which is thoroughly effective in preventing theft of a vehicle.